GeoSpectrum Intro
Seismic Exploration for Fractured Lower Dakota Alluvial Seismic Exploration for Fractured Lower Dakota Alluvial Gas Sands, San Juan Basin, New MexicoGas Sands, San Juan Basin, New Mexico
U.S. Department of Energy Contract No. DE-AC-00NT40697U.S. Department of Energy Contract No. DE-AC-00NT40697
Contractor:Contractor: GeoSpectrum, Inc., Midland, Texas GeoSpectrum, Inc., Midland, Texas
Industry Partner: Industry Partner: Burlington Resources, Farmington, New MexicoBurlington Resources, Farmington, New Mexico
Principal Investigator: Principal Investigator: Dr. James J. Reeves, Ph.D., P.G., P.E.Dr. James J. Reeves, Ph.D., P.G., P.E.Project Manager: Project Manager: W. Hoxie Smith, M.S.W. Hoxie Smith, M.S.
Regional Map of 4 Corners AreaRegional Map of 4 Corners Area
After James A. Peterson, et al (1965) Figure 1
MCFGMCFG
Cumulative GasCumulative Gas
Base Map / Dakota Gas Production
Figure 2
Greenhorn-Burro Canyon Type Log
(After Whitehead, 1993) Figure 3
Prospect Development MethodologyProspect Development Methodology
Table 1
Bubble size is best 12-months production
Hydrocarbon Pore Volume vs. Porosity-Thickness
55
27
31
28
55E
47
15 30
41
Figure 5
Number of Dakota Fractures vs. Best 12 Month Production Indicator
Number of Dakota Fractures
Bes
t 12
Mo
nth
s P
rod
uct
ion
In
dic
ato
r
Figure 6
Seismic Line Sample
DKOT
MRSN
ENSS
Figure 7
Lineaments in Seismic SectionCoherency Slice @ 1350 ms
Figure 8a
Lineaments in Seismic SectionCoherency Slice @1350 ms (3D View)
Figure 8b
Lineaments in Seismic SectionAll Azimuth Frequency @ Timeslice 1308 ms
Figure 9a
Lineaments in Seismic SectionAll Azimuth Frequency @ Timeslice 1308 ms (3D View)
Figure 9b
Dinosaur Ridge Dakota
Photo credit John M. Ghist
Dinosaur Ridge Near Morrison, Colorado
Figure 10
Lower Dakota Seismic Lineamentswith Borehole Breakout Rose Diagrams
Figure 11
Lower Dakota Seismic Lineament DensityLower Dakota Seismic Lineament Density
Lineaments Per Grid
900 x 900 ft Grid
Fractured Reservoir Leads
I H G F
E
D
CB
A
Lower Dakota Rose Diagrams
Figure 12
Lower Dakota Seismic StructureLower Dakota Seismic Structure
Subsea Depth ftSubsea Depth ft
Showing Lower Dakota Rose Diagrams and Seismic Lineaments
Figure 14
Multiple Scales of Observation
Dakota Production Trend
Regional Scale
Seismic Lineaments
Field Level Scale
Borehole Image Data
Localized Scale
Dakota Production Mapping (after C. F. Head, June 2001)Seismic Lineaments w/ Lower
Dakota Rose Diagrams Figure 13
55e (48)
31 (503)
27 (105) 48 (107)
28 (1710)
55 (711)
47 (73)
15 (45)
41 (33)
30 (66)
Co-located Co-kriged Dakota Fractures
Dakota FracturesDakota Fractures
With Upper Dakota Rose Diagrams
SITE 3
SITE 4
SITE 1
SITE 2
Azimuth Dependent Dix Interval Velocity DifferenceFigure 28
Wellbore Fracture Data vs. Seismic Velocity Data
Wellbore Fracture Data vs. Velocity AnisotropyIn
terv
al
Vel
oci
ty (
az 1
45-
55)
ft/s
ec(S
EIS
MIC
or
Mac
ro-S
cale
Mea
sure
men
t)
Dakota Fractures(WELLBORE or Micro-Scale Measurement)
Figure 29
Thickness ftThickness ft
Lower Dakota Seismic Isopach
Figure 16
Lower Dakota Seismic Coherency / Channel Stratigraphy
CoherencyCoherency
Figure 17
y = 128459x + 4314.6
r2 = 0.6580
r = 0.8111
Sei
smic
Am
pli
tud
e
Lower Dakota Clay Volume
Lower Dakota Clay Volume vs. Seismic Amplitude Data(w/ Sg Bubbles)
Figure 18
Co-located Co-kriged Clay Volume
Percent Clay
Near Trace Seismic Amplitude
98%
79%87%
40%
56%75%
61%
90%
59%
(With Average Water Saturation Bubbles)
Figure 19a
Co-located Co-kriged Clay Volume
Percent Clay
Near Trace Seismic Amplitude
Showing Lower Dakota Rose Diagrams and Seismic Lineaments
Figure 19b
Lower Dakota Acoustic Impedance
AC IMPAC IMP
ft/ms-g/ccft/ms-g/cc
Lower Dakota Rose Diagrams Figure 20
Amplitude vs. Angle of Incidence
Class 1, 2, & 3 AVO anomalies
From Rutherford and Williams (1989) Figure 23
AVO Modeling for Lower Clay Volume WellsAVO Modeling for Lower Clay Volume Wells
#55
60% Sg
3% clay
710 mcfd
#28
44% Sg
8% clay
1710 mcfd
#31
39% Sg
13% clay
502 mcfd
These 3 wells wells have the best production indicators in the study area
Figure 22a
AVO Modeling for Higher Clay Volume WellsAVO Modeling for Higher Clay Volume Wells
#47
21% Sg
18% clay
73 mcfd
#15
13% Sg
14% clay
45 mcfd
#30
10% Sg
17% clay
66 mcfd
Figure 22b
y = 278.59x - 188.43
r2 = 0.7946
r = 0.8914
Ph
ase
Dif
fere
nce
(D
egre
es)
Gas Saturation (%)
Lower Dakota Gas Saturation vs. Phase Difference(w/ Clay Volume Bubbles)
Figure 24
Near-Far Phase(No Clay Editing)
Range:
–15 to –85 degrees
No clay editing
Figure 25a
Near-Far Phase(w/ Clay Editing)
Range:
–15 to –85 degrees
With clay editing
Figure 25b
Lower Dakota Seismic Phase Difference
Percent Percent
Gas SaturationGas Saturation
Co-located Co-Kriged Lower Dakota Gas Saturation
Shown with Lower Dakota Rose Diagrams Figure 26
AVO Modeling/Gather Well #28 & Site 4AVO Modeling/Gather Well #28 & Site 4
Site #4Well #28
Figure 27
Composite Map Composite Map Lower Dakota Reservoir AttributesLower Dakota Reservoir Attributes
AREAS
Gas, low clay, velocity anisotropyGas, low clay, velocity anisotropy
Gas, low velocity anisotropyGas, low velocity anisotropy
Gas, high clayGas, high clay
Gas, high clay, low velocity Gas, high clay, low velocity anisotropyanisotropy
No gasNo gas
No gas, low velocity anisotropyNo gas, low velocity anisotropy
No gas, high clayNo gas, high clay
LINES
Black LinesBlack Lines…lineaments…lineaments Thick Black Clouds… outline of Thick Black Clouds… outline of higher lineament densityhigher lineament density
4 ATTRIBUTESClay Content Lineament Density Velocity AnisotropyPhase Difference/Gas Saturation
Figure 30
Conclusions / Prospect Drilling ResultsConclusions / Prospect Drilling Results
Well No.
Date Completed
Clay Volume
Gas Saturation
Velocity Anisotropy
Initial Production (MCFGPD)
52 01/2004 Good Good Excellent 4000
28E 05/2004 Good Good Good 2000
31E 06/2004 Good Good Good 850–2000
53 04/2004 Poor No AVO Attribute
Excellent Declined to 250
AcknowledgementsAcknowledgementsGeoSpectrum, Inc. would like to thank the following people for
their contributions to this study:
U.S. Department of Energy for the majority of the funding of this study.
The industry operator and their employees and associates who provided data and interpretations which greatly benefited this project.
Dr. James J. Reeves, for his conscientious work as Principal Investigator.
Mr. W. Hoxie Smith, who diligently served as Project Manager for this study.
Mr. W. Roger Smith, who abstracted the Play Geology section of this paper from the operator’s well files.
Mr. Don Zimbeck, for his professional seismic data processing.
Mr. Jim Oden, who provided his expert seismic interpretation.
Mr. Jeff Kane, who’s petrophysical analysis was invaluable.
Ms. Sylvia Chamberlain, who was responsible for exploratory data analysis and AVO analysis / modeling.
Mark E. Semmelbeck, Ph.D., for his proficient production data analysis.
Mr. Mark M. Gygax, for his engineering review of data and results and efforts in putting this slide show together.
DOE technical contract managers, who’s timeliness and assistance has been greatly appreciated.
President and Technical ManagerJames J. Reeves, Ph.D., P.G., P.E.
Dr. Reeves has his degrees from the Colorado School of Mines. He is a registered Professional Engineer in the State of Texas. Dr. Reeves' industry experience includes work with Gulf Oil Corporation and Pecten International Company as an Exploration Geophysicist. As an Assistant Professor of Geology at the University of Texas of the Permian Basin, he taught several courses on finite difference and finite element numerical modeling. He also conducted research in seismic data processing and interpretation of seismic data at UTPB, and as an Associate Research Professor for Texas Tech University. Dr. Reeves has served as a Principal Investigator and Project Geophysicist in two Department of Energy studies focusing on the integration of geological, geophysical, and reservoir engineering data to optimize oil and gas production.
Mr. Smith has over 20 years of industry experience, including 9 years with Atlantic Richfield Company (ARCO) and 4-years with Dawson Geophysical Company before co-founding GeoSpectrum Inc. He has managed several large industry reservoir projects and served as the Project Manager for an integrated reservoir characterization study conducted through the U.S. Department of Energy's Oil & Gas Program. Mr. Smith has been the featured speaker at numerous professional society meetings including national meetings of the Society of Exploration Geophysicists, American Association of Petroleum Geologists, and the Society of Petroleum Engineers. He received his B.S. degree in Geology from Colorado State University and his M.S. degree in Geology from the University of Texas of the Permian Basin.
Vice President and Project Coordinator W. Hoxie Smith, M.S.